Post by djoser-xyyman on Aug 15, 2014 14:34:37 GMT -5
This dataset also corroborate the fact that E1b1b(M-35) is found in one of the oldest population in Africa. Proving the ancient connection between Berbers and click speakers with possible origin of both groups near the Nile Great Lakes in the very distant past.
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Complete Khoisan and Bantu genomes from southern Africa - Stephan C. Schuster, Moorjani 2010
wide, including 13,146 novel amino acid variants. In terms of nucleotide substitutions, the Bushmen seem to be, on average, more different from each other than, for example, a European and an Asian. Observed genomic differences between the hunter-gatherers and others may help to pinpoint genetic adaptations to an agricultural lifestyle.
The Bantu individual is Archbishop Desmond Tutu (ABT), who represents Sotho-Tswana and Nguni speakers (from the broad Niger–Congolanguages), the twolargest southernAfrican Bantugroups. As the genomes of our study participants were expected to diverge
Consistent with the view that southern Africans are among the most divergent human populations, we identified more SNPs in KB1, and to a lesser extent inABT, than have been reported in other individual human genomes (Fig. 2 and Table 1), although a portion of the variation in SNP numbers may stem from differences in technology and levels of coverage. The number of SNPs that are novel (that is, not previously seen in other individuals) is far higher for KB1 and ABT than for other individual whole genomes (Table 1). KB1 and ABT each have approximately 1 million SNPs that are NOT shared with each other or with the published Yoruban, Asian or European complete genomes4–8 (Fig. 2). In
Thus, very few of the novel differences in KB1’s genome are ancestral nucleotides retained in the Bushmen; instead, the vast majority are changes that accumulated since the Bushmen lineage diverged from other human populations
high percentages of heterozygous SNPs (59% and 60%, respectively), as expected. This discrepancy underscores the INADEQUACY of current SNP arrays for analysing southern African populations.
as direct typing of a 238-bp indel13 (Supplementary Fig. 5) confirm that KB1 is heterozygous for the 17q21.3 H2 haplotype, a SURPRISING finding because the H2 allele is found at low frequencies in non-European populations12. Read depth and array-CGH indicate that the H2 allele carried by KB1 does not contain the 75-kb duplication present on all analysed European H2 alleles14–16 (Supplementary Fig. 6a, b). The KB1 H2haplotypemay represent the ancestral sequence and structure of the H2 haplotype that was present in African populations BEFORE ITS INCREASED FREQUENCY in European and Middle Eastern populations12. We also observed a --- It is possible that increased SNP frequency in these genomic regions could drive phenotypic changes in humans
lactase persistence allele (a functional promoter variant in the LCT gene) and of the SLC24A5 allele associated with light-coloured skin. In other instances, agreement with the human reference sequence is informative, such as the lack of the African-specific Duffy null (DARC) malaria-resistance allele17. The lack of malaria-resistance alleles in the Bushmen populations might have significant consequences on an already dwindling population of well-adapted foragers, when forced into a farming lifestyle that brings increased pathogen loads17. Therefore, these genetic markers may allow for the tracing of the rate of human adaptation in changing environments18
(see Supplementary Information). Although a number of SNPs observed in the Bushmen have been related to phenotypes in other ethnic groups in the literature and online databases, one should REMAIN SCEPTICAL about the validity of untested associations. In the Supplementary Information, we
